Contaminant separation from a rotary vane pump

ABSTRACT

A rotary pump of the sliding vane type is shown with a plurality of passageways located in the rotor of the pump to provide cleaned fluid for use as a lubricant, etc. The passageways are connected on one end to the pumping chambers of the pump and are designed to effectively store fluid trapped therein for a number of revolutions of the rotor, thereby permitting contaminant particles within the passageways to be centrifuged back into the main flow stream of the pump. Cleaned fluid is delivered to a chamber at the opposite end of the passageway from which it is used to maintain the sliding vanes in position and also as a lubricant.

United States Patent Inventor Carroll W. De Lisse Cincinnati, Ohio Appl.No. 006,378

Filed Jan. 28, 1970 Patented June 29, 1971 Assignee General ElectricCompany CONTAMINANT SEPARATION FROM A ROTARY VANE PUMP Primary Examiner-Robert M. Walker Att0rneys Derek P. Lawrence, Thomas .1. Bird, Jr., LeeH. Sachs, Frank L. Neuhauser. Oscar B. Waddell and Joseph B. FormanABSTRACT: A rotary pump of the sliding vane type is shown with aplurality of passageways located in the rotor of the pump to providecleaned fluid for use as a lubricant, etc. The passageways are connectedon one end to the pumping chambers of the pump and are designed toeffectively store fluid trapped therein for a number of revolutions ofthe rotor, thereby permitting contaminant particles within thepassageways to be centrifuged back into the main flow stream of thepump. Cleaned fluid is delivered to a chamber at the opposite end of thepassageway from which it is used to maintain the sliding vanes inposition and also as a lubricant.

PATENTEDJUN29|97I 3,589,841

sum 2 BF 2 v INVENTOR. CARROLL W. DELISSE AGENT- CONTAMINANT SEPARATIONFROM A ROTARY VANE PUMP BACKGROUND OF THE INVENTION This inventionrelates generally to rotary vane pumps and, more particularly, to anapparatus for eliminating contaminant particles from such a pump.

Rotary expansion motors or pumping devices have been in use for manyyears. One common type of such pump works on a sliding vane principle.An eccentrically mounted rotor having radially outwardly extending vanesis located within a stator such that the vanes are resiliently urgedagainst the inner wall of the stator to provide a complete seal betweenthe wall and the vanes and to thus provide a plurality of variablevolume chambers between each pair of adjacent vanes. Fluid is injectedinto the large volume chambers and is forced out as the volume of thechamber decreases with rotation of the rotor. The shaft of the rotor isnormally coupled to an external source of power for driving the same.

In designing sliding vane-type pumps, designers manytimes utilize filmsof the fluid which is being pumped to support the various types ofmembers located in the pumps which move relative to each other. Forexample, the sliding vane itself is occasionally provided with a film ofthe fluid in order tosubstantially eliminate friction between the vaneand the rotor which is carrying it. When a fluidic film is utilized insuch a manner, however, it is necessary to eliminate any contaminants inthe film prior to such usage. Pump designers in the past have usedmechanical barrier screens to eliminate contaminants from such fluidicfilms. These screens have a number of basic disadvantages, however, suchas the requirement of periodic removal for cleaning and/or replacement.The use of such a screen also requires a preliminary design study tominimize the penalty imposed by holding capacity, initial cost, and costof cleaning and/or replacement in terms of the flow range desired andthe trapped particle size of the screen needed.

For the above reasons, various flow path configurationshave been devisedto separate solid particles from fluids by utilizing the diflerentinertial characteristics of the particles. Devices of this type,however, invariably consume power from either the flow stream, a drivingpower source, or both. Such devices are also unpredictable over thelarge flow ranges occasionally associated with some pumping devices.

SUMMARY OF THE INVENTION It is an object of the present invention,therefore, to provide a continuous supply of decontaminated fluid for arotary-type pump without the necessity of cleaning and/or replacing afilter unit.

It is a further object of the present invention to provide such anapparatus which has predictable operational characteristics overlargeflow ranges and efficient separation characteristics over theentire range of operation.

Briefly stated, the objects of this invention are achieved by providinga plurality of passageways in the rotor of the rotary pump, whichpassageways are in fluidic flow cooperation with the expansion chambersof said pump. The passageways are designed to effectively store fluidtrapped therein for a number of revolutions of the rotor. This permitscentrifugal separation of particles carried by the fluid into thepassageways and also permits the centrifuged particles to be dischargedinto the main flow stream of the rotary pump. The cleaned fluid is thendischarged from the passageway into a cavity from which it can be routedto any desired location.

DESCRIPTION OF THE DRAWINGS While the specification concludes withclaims particularly pointing out the subject matter of the inventionwhich is sought to be covered, the invention may be understood from thefollowing description of a preferred embodiment, given in connectionwith the accompanying drawings, in which:

FIG. 1 is an exploded view, partially broken away, of a sliding vanerotary pump constructed in accordance with this invention;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.

FIG. 3 is an exploded view, partially broken away, of an alternativeembodiment; and

FIG. 4 is a cross-sectional view taken generally along line 4-4 of FIG.3.

DESCRIPTION OF A PREFERRED EMBODIMENT 7 Referring to the drawingswherein like numerals correspond to like elements throughout, a slidingvane-type rotary pump, generally designated by the numeral 10, is shownas comprising a first pressure plate 12, a second pressure plate 14, arotor 16 and an eccentric stator 18. The rotor 16 comprises a solidcylindrical member having a plurality of radial slots 20 locatedtherein. Suitably located for reciprocation within the slots 20 are alike number of sliding vanes 22.

The rotor 16 is positioned so that it is capable of rotation within thestator 18 as shown in both FIGS. 1 and 2. The stator 18 comprises agenerally hollow cylinder having a noncircular, eccentric inner wall 24.As is best shown in FIG. 2, the wall 24 cooperates with the outer endsof the vanes 22 to provide a plurality of pumping chambers, generallydesignated by the numeral 26, which are of varying volume. Each chamber26 is outlined by the sides of a pair of adjacent vanes 22, the wall 24,the outer surface of the rotor 16, and the pressure plates 12 and 14.The vanes 22 are maintained in sealed relationship with the wall 24 bysome means in order to prevent the flow of fluid therebetween. The vanes22 may be provided with suitable sealing members at their tips as isgenerally known.

The rotor 16 is provided with rotary motion by a suitable connection toan external source of power as through a spline 28 located within therotor 16. Inlet fluid, generally designated by the arrows labeled I,enters the increasing volume between a pair of adjacent vanes 22 throughinlets 30, provided in either the pressure plates l2, 14 or in thestator 18. In either case, the volume of the chamber 26 which iscarrying the fluid remains constant while the fluid is trapped andtransported to a discharge area where the volume between adjacent vanes22 decreases and thereby forces the fluid to leave the pump 10 throughports 32 located in the pressure plate 12, one of which is shown inFIG. 1. The discharge fluid is shown schematically in FIG. 1 by thearrows labeled (D). The decreasing volume of the chambers 26 is providedby the eccentric shape of the wall 24, as is shown best in FIG. 2.

As thus far described, the pump 10 is of conventional construction withall of the elements thereof being known to those skilled in the art. Indesigning a sliding vane-type pump such as the one previously described,some means must be provided for maintaining the sliding vanes 22 incontact with the wall 24 at all times. Designers in the past haveutilized spring members located within the slots 20 in some cases, andinother cases have utilized fluid pressure to maintain the vanes 22 inproper position. The present application, while not limited thereto, isespecially suited for use with the latter-type design wherein fluidpressure is used to maintain the vanes 22 in sealed contact with thewall 24. The present invention is concerned with providing this fluid tothe base of the vanes 22 for the abovedescribed purpose while at thesame time eliminating contaminant particles from the fluid so that it issuitable forthe above purpose. In addition, this cleaned fluid may beused as a fllm to support the various kinds of members within a pumpwhich move relative to each other.

In light of the above, the rotor 16 is provided with a plurality ofpassageways 34, shown being located between each pair of vanes 22. Oneend 35 of the passageway 34 is in fluidic flow cooperation with thechamber 26, as shown in FIG. I, while the opposite end 36 is in fluidicflow cooperation with a first conduit 37, a plurality of which areradially positioned within the pressure plate 14. The conduits 37 are,in turn, in fluidic flow cooperation with a number of second conduits38, also located within the pressure plate 14 and spaced radiallyinwardly from the conduits 37. The conduits 38 are provided to deliverthe cleaned fluid to the base of the slots 20 in order to maintain thevanes 22 in sealed relationship with the wall 24.

As shown in FIG. 1, a portion of the discharge fluid (D) will enter thepassageways 34 instead of exiting through the ports 32. That portion offluid which enters the passageways 34 is generally designated by thearrow (C). The passageways 34 are constructed with a volume that issufficient to effectively store the fluid (C) for a number ofrevolutions of the rotor 16. The passageways 34 are also constructed atan angle which is sufficient to induce large angular accelerations andthereby cause a separating action to occur between the fluid (C) andrelatively dense particles which may be entrained therein. Thus,rotation of the rotor 16 provides centrifugal separation of anyparticles which may have been carried by viscous action along with fluid(C) into the passageways 34. These particles are centrifuged back intothe main discharge flow stream where they exit through the ports 32along with the main discharge flow (D). Cleaned fluid (labeled E) isthus provided at the lower end of the passageways 36 and exits throughthe plurality of openings 36 within the rotor 16 from which it passes tothe conduits 37 located within the pressure plate 14.

In addition to providing this cleaned fluid for pressing the vanesagainst the wall 24, the pump can also be made to deliver the cleanedfluid as a film to any other bearing members required for its operation.If desired, the cleaned fluid could also be provided to other devices,such as controlling valves, fluidic devices, or jet pipes which requireclean fluid for best operation.

Referring now to FIGS. 3 and 4, an alternative form of rotary pumpcapable of utilizing applicants particle separation passageways is shownand labeled with the numeral 50. The rotary pump 50 includes an annularrotor or carrier member 52 having a plurality of slots 54 locatedtherein which carry pumping elements 56 and which is surrounded by a cammember 58. The cam member 58 has an inner cam surface 60 along which thepumping elements 56 move as the rotor or carrier member 52 is rotated.The pumping elements 56 are preferably cylindrical members which aresized so as to be capable of movement radially inwardly and outwardlywithin the slots 54. This radial movement of the pumping elements 56 iscaused by engagement with the cam surface 60 during rotation of therotor member 52.

The pumping elements 56 are further sized so as to engage the sides ofthe slots 54 in a generally fluidically sealed manner. In this way, theslots 54 and the pumping elements 56 form a plurality of pumpingchambers 62 which are of variable volume. As clearly shown in FIG. 4,the volume of the pumping chambers 62 decreases as the pumping elements56 move radially inwardly within the slots 54, and increases as thepumping elements 56 move radially outwardly.

Referring now to FIG. 3, the rotor member 52 and the cam member 58 aresurrounded by a pair of end plates 64 and 65 which form the ends of therotary pump 50. The end plates 64 and 65 are connected to the cam member58 by any suitable means in order to form the ends of the pumpingchambers 62. The end plate 64 includes a pair of inlets 66 fordelivering a fluid to the pumping chambers 62 at locations wherein thevolume of the pumping chambers 62 is increasing, while the end plate 65includes a pair of outlets 68 (one of which is shown) which receivefluid from the pumping chambers 62 during periods when the volumethereof is decreasing.

As further shown in the drawings, the rotor member 52 is furtherprovided with a plurality of passageways 70, an inlet end 72 of whichlies in communication with the pumping chambers 62 while an outlet end74 lies within one face of the rotary member 52. The outlet ends 74 ofthe passageway 70 lie in communication with a chamber 76 formed withinthe end plate 64.

In operation, the rotor member 52 is coupled to a suitable source ofexternal power which provides rotation thereto and fluid is delivered tothe pumping chambers 62 through the inlets 66 formed in the end plates64. As the rotor member 52 rotates, the pumping elements 56 engage theinner cam sur face 60 of the cam member 58 and are moved radiallyinwardly thereby. This causes an increase in the pressure of the fluidwithin the pumping chambers 62 until it exits through the pair ofoutlets 68 in the second end plate 65.

A portion of the fluid within the pumping chambers 62, however, willenter the inlet end 72 of the passageways 70 instead of exiting throughthe outlets 68. The passageways 70 (similar to the passageways 34 shownin FIGS. 1 and 2) are formed with a volume that is sufficient toeffectively store fluid entrapped therein for a number of revolutions ofthe rotor member 52. Because of this, any contaminant particles whichmay have been carried by this viscous action into the passageways 70will be centrifuged back into the pumping chamber 62 throughthe inletends 72 of the passageways 70. These contaminant particles will then bedischarged through the outlets 68 along with the main discharge flow.

In this manner, a supply of cleaned fluid is provided at the outlet ends74 of the passageways 70. This cleaned fluid may then be stored withinthe chamber 76 and utilized for any suitable purpose. For example, thecleaned fluid could be delivered to the area between the rotor member 52and the cam surface 60 to act as a film to prevent friction between thecam surface 60 and the pumping elements 56. Also, as previouslymentioned with respect to FIGS. 1 and 2, the cleaned fluid could bedelivered to any fluidically operated member which requires contaminantfree fluid.

The actual design of the passageways 34 and 70 would, of course, dependupon the viscosity of the fluid which is being pumped and would alsodepend upon the size of the particles which are desired to becentrifuged. It can readily be seen from the above description thatapplicant has provided a simple source of cleaned fluid for use in anyrotary pump. In addition, applicant has eliminated the need for periodiccleaning or replacement of presently used screens insofar as centrifugedparticles are deposited right back in the main dischargestream of thepump and are thus eliminated from the pump. The operationalcharacteristics of applicants pump are predictable over large flowranges and separation efficiency would actually increase withdiminishing, flow as the number of particles entering the passageways 34would decrease with diminishing flow. While applicant's separationdevice has been shown in connection with two types of rotary pumps, itshould be readily apparent that it would perform in a similar manner inany type of rotary pump. Such an operation would merely require theaddition of a set of suitable cavities in any rotating member and asuitable means to extract the flow from the cavity or cavities. 1

What I claim as new and sought to be covered by Letters Patent of theUnited States is:

I. In a rotary pump having a rotor, a stator, a pumping chamber definedby the interaction of said rotor and said stator,

an inlet in fluidic flow cooperation with said pumping chamber,

an outlet in fluidic flow cooperation with said pumping chamber, theimprovement which comprises at least one passageway located within saidrotor,

said passageway having a first opening located at one end thereof and asecond opening located at the opposite end thereof,

said first opening lying in fluidic flow cooperation with said pumpingchamber,

said passageway being dimensioned such that particles entrapped thereinare centrifuged into said pumping chamber,

thereby providing cleaned fluid at said second opening.

2. The rotary pump recited in claim 1 wherein said second opening liesin fluidic flow cooperation with a conduit which receives said cleanedfluid.

3. The rotary pump recited in claim 2 wherein said rotor comprises acylindrical member having a plurality of radial slots located thereinand a plurality of vanes located within said slots, said vanes beingcapable of reciprocal movement within said slots.

4. The rotary pump recited in claim 2 wherein said rotor comprises acylindrical member having a plurality of radial slots therein and aplurality of pumping elements located within said slots,

said pumping elements being capable of radial movement within saidslots, and

said pumping elements engaging the sides of each slot to thereby definea variable volume pumping chamber within each of said slots.

5. The rotary pump recited in claim 3 wherein said conduit lies influidic flow cooperation with said slots.

6. The rotary pump recited in claim 5 wherein said stator comprises ahollow cylindrical member having a noncylindrical, eccentric inner wallwhich surrounds said rotor,

said vanes being maintained in sealed engagement with said innerwall,

thereby providing a plurality of variable area pumping chambers, one ofwhich is located between each adjacent pair of said vanes.

7. The rotary pump recited in claim 6 wherein said rotor includes aplurality of said passageways,

said passageways being provided between each adjacent pair of vanes.

8. The rotary pump recited in claim 7 wherein said cleaned fluid isutilized to maintain said vanes in sealed engagement with said innerwall.

9. The rotary pump recited in claim 7 further comprising bearing meansassociated with said rotor, wherein said cleaned fluid is delivered tosaid bearing means.

1. In a rotary pump having a rotor, a stator, a pumping chamber definedby the interaction of said rotor and said stator, an inlet in fluidicflow cooperation with said pumping chamber, an outlet in fluidic flowcooperation with said pumping chamber, the improvement which comprisesat least one passageway located within said rotor, said passagewayhaving a first opening located at one end thereof and a second openinglocated at the opposite end thereof, said first opening lying in fluidicflow cooperation with said pumping chamber, said passageway beingdimensioned such that particles entrapped therein are centrifuged intosaid pumping chamber, thereby providing cleaned fluid at said secondopening.
 2. The rotary pump recited in claim 1 wherein said secondopening lies in fluidic flow cooperation with a conduit which receivessaid cleaned fluid.
 3. The rotary pump recited in claim 2 wherein saidrotor comprises a cylindrical member having a plurality of radial slotslocated therein and a plurality of vanes located within said slots, saidvanes being capable of reciprocal movement within said slots.
 4. Therotary pump recited in claim 2 wherein said rotor comprises acylindrical member having a plurality of radial slots therein and aplurality of pumping elements located within said slots, said pumpingelements being capable of radial movement within said slots, and saidpumping elements engaging the sides of each slot to thereby define avariable volume pumping chamber within each of said slots.
 5. The rotarypump recited in claim 3 wherein said conduit lies in fluidic flowcooperation with said slots.
 6. The rotary pump recited in claim 5wherein said stator comprises a hollow cylindrical member having anoncylindrical, eccentric inner wall which surrounds said rotor, saidvanes being maintained in sealed engagement with said inner wall,thereby providing a plurality of variable area pumping chambers, one ofwhich is located between each adjacent pair of said vanes.
 7. The rotarypump recited in claim 6 wherein said rotor includes a plurality of saidpassageways, said passageways being provided between each adjacent pairof vanes.
 8. The rotary pump recited in claim 7 wherein said cleanedfluid is utilized to maintain said vanes in sealed engagement with saidinner wall.
 9. The rotary pump recited in claim 7 further comprisingbearing means associated with said rotor, wherein said cleaned fluid isdelivered to said bearing means.